RLC Circuit

Contents

symbolic

clear
R1 = sym('R1');
L1 = sym('L1');
C1 = sym('C1');
Vs = sym('Vs');
% vector of unknowns
V1 = sym('V1');
V2 = sym('V2');
V3 = sym('V3');
Iv = sym('Iv');
IL = sym('IL');
y = sym([V1; V2; V3; Iv; IL]);

Build system

Gm = nmAcc(1,2,1/R1,sym(zeros(5,5)));
Cm = nmAcc(3,0,C1,sym(zeros(5,5)));
Is = sym(zeros(5,1));
m = 4;
Gm = mnaVsrc(m,1,0,Gm);
Is(m) = Vs;
m = 5;
Gm = mnaVsrc(m,2,3,Gm);
Cm(m,m) = -L1;

% show results
disp('y (unknowns)');
pretty(y);
disp('Gm');
pretty(Gm);
disp('Cm');
pretty(Cm);
disp('Is (rhs)');
pretty(Is);
y (unknowns)

  +-    -+
  |  V1  |
  |      |
  |  V2  |
  |      |
  |  V3  |
  |      |
  |  Iv  |
  |      |
  |  IL  |
  +-    -+
Gm

  +-                       -+
  |    1      1             |
  |   --,  - --,  0, 1,  0  |
  |   R1     R1             |
  |                         |
  |     1    1              |
  |  - --,  --,   0, 0,  1  |
  |    R1   R1              |
  |                         |
  |    0,    0,   0, 0, -1  |
  |                         |
  |    1,    0,   0, 0,  0  |
  |                         |
  |    0,    1,  -1, 0,  0  |
  +-                       -+
Cm

  +-                  -+
  |  0, 0,  0, 0,  0   |
  |                    |
  |  0, 0,  0, 0,  0   |
  |                    |
  |  0, 0, C1, 0,  0   |
  |                    |
  |  0, 0,  0, 0,  0   |
  |                    |
  |  0, 0,  0, 0, -L1  |
  +-                  -+
Is (rhs)

  +-    -+
  |   0  |
  |      |
  |   0  |
  |      |
  |   0  |
  |      |
  |  Vs  |
  |      |
  |   0  |
  +-    -+

state equations

stateeq
x (state variable)

  +-    -+
  |  V3  |
  |      |
  |  IL  |
  +-    -+
A

  +-            -+
  |          1   |
  |    0,   --   |
  |         C1   |
  |              |
  |     1    R1  |
  |  - --, - --  |
  |    L1    L1  |
  +-            -+
B

  +-    -+
  |   0  |
  |      |
  |  Vs  |
  |  --  |
  |  L1  |
  +-    -+
C

  +-        -+
  |  0,  0   |
  |          |
  |  0, -R1  |
  |          |
  |  1,  0   |
  |          |
  |  0,  -1  |
  |          |
  |  0,  1   |
  +-        -+
D

  +-    -+
  |  Vs  |
  |      |
  |  Vs  |
  |      |
  |   0  |
  |      |
  |   0  |
  |      |
  |   0  |
  +-    -+
y

  +-    -+
  |  V1  |
  |      |
  |  V2  |
  |      |
  |  V3  |
  |      |
  |  Iv  |
  |      |
  |  IL  |
  +-    -+
C*x+D

  +-            -+
  |      Vs      |
  |              |
  |  Vs - IL R1  |
  |              |
  |      V3      |
  |              |
  |      -IL     |
  |              |
  |      IL      |
  +-            -+